"Are the numeric values of these character array pairs defined anywhere on the COM application,"
No. The constants are only named in the VBA environment through the intellisense link or in the doc.
There isn't any link between the MATLAB code editor and VBA by which that connection is made although I suppose if one were ambitious-enough, one could write an extension (or is the TMW editor even user-extensible?).
It is a real inconvenience in using COM in MATLAB, agreed.
